Abstract

This document contains the results of the energy usage optimization in HEMAV test-bed. It has been developed as part of an internship in HEMAV, a young European company based in Molins de Rei, Barcelona dedicated to make safe civil services with RPAS technology. The main objectives of this study are increase the flight time of the hexacopter by studying the behaviour of different propellers and increasing or decreasing the number of batteries. And, finally, study the influence of performing different paths in the autonomy. First of all, it is proposed to create a data base where after each mission the whole data collected would be downloaded, because, then, this data could be analysed. And doing this, HEMAV would be able to know what the most usual manoeuvres and operations are and they could try to increase their efficiency. The main conclusion extracted from the propellers study is that the material of the propeller does not have a notable effect in terms of thrust. But when looking at the consumption, it can be seen a positive effect, less consumption, when the material is carbon fibre instead of nylon. In addition, during the propellers study it was known that pitch is one of the important factors, smaller propeller pitch means more thrust. But, also, it was known that for bigger propeller pitches the necessary acceleration to change from a lower velocity to a higher velocity is smaller than in the contrary case. After the propellers study, the effect of having more batteries in the platform was analysed and the main conclusion is that there is a point where although more batteries are added, the flight time do not increase more. This point is around the 1246 gr of the propeller test battery, and it coincides for the three propellers. So doubling the battery capacity does not mean doubling the hover flight time. Also, the author realized, in the dynamic test, that the procedure that has to be followed before performing a flight is very large. And that there are a lot of things that should be taken into account, such as sensors implementation, check that everything is safe and works properly, find a place to fly, and check that all is still running before doing the test. Finally, it was verified that the hexacopter consumes a lot when it has to maintain the same position, the same as when there are sudden changes in velocity.